Multiple diaphragm pump

Patent metadata

Field	Value
Publication number	US-11221004-B2
Application number	US-201815963770-A
Country	US
Kind code	B2
Filing date	Apr 26, 2018
Priority date	Jul 12, 2017
Publication date	Jan 11, 2022
Grant date	Jan 11, 2022

Abstract

A diaphragm pump assembly can include a pump drive chamber, a first pump diaphragm chamber, and a second pump diaphragm chamber. The assembly can include a pump motor configured to rotate a motor shaft extending into the pump drive chamber. The assembly can include a cam connected to the motor shaft and configured to rotate in response to rotation of the motor shaft. The assembly can include a drive yoke having a yoke frame and a yoke pocket having a first wall and a second wall parallel and opposite the first wall. First and second pistons can connect to the drive yoke and to first and second diaphragms, respectively. The diameter of the cam can be less than and within 5% the width of yoke pocket and the yoke can be configured to move the pistons along a straight line.

First claim

What is claimed is:

1. A diaphragm pump assembly comprising:
an assembly inlet;
an assembly outlet;
a first pump chamber positioned in a first fluid path between the assembly inlet and outlet;
a second pump chamber positioned in a second fluid path between the assembly inlet and outlet;
a first diaphragm positioned at least partially within the first pump chamber, the first diaphragm having a perimeter sealingly connected to one or more walls of the first pump chamber;
a second diaphragm positioned at least partially within the second pump chamber, the second diaphragm having a perimeter sealingly connected to one or more walls of the second pump chamber;
a first piston connected to the first diaphragm, the first piston movable linearly;
a second piston connected to the second diaphragm, the second piston movable linearly;
a pump drive chamber positioned between the first pump chamber and the second pump chamber;
a drive yoke connected to both the first and second pistons and positioned within the pump drive chamber, the drive yoke having a first drive wall and a second drive wall parallel to and opposing the first drive wall;
a motor;
a straight motor drive shaft having a first end connected to the motor and a second end extending through the pump drive chamber;
an offset cam having a cam diameter, the offset cam connected to the motor drive shaft and configured to rotate in unison with the motor drive shaft; wherein:
the offset cam is configured to push the drive yoke toward the first pump chamber during a first portion of one rotation of the straight motor shaft and to push the drive yoke toward the second pump chamber during a second portion of one rotation of the straight motor shaft;
movement of the drive yoke toward the first pump chamber forces a portion of the first diaphragm to move and to increase pressure in the first pump chamber;
movement of the drive yoke toward the first pump chamber forces a portion of the second diaphragm to move and to reduce pressure in the second pump chamber;
movement of the drive yoke toward the second pump chamber forces a portion of the first diaphragm to move and to reduce pressure in the first pump chamber;
movement of the drive yoke toward the second pump chamber forces a portion of the second diaphragm to move and to increase pressure in the second pump chamber;
a first one way valve positioned in a fluid path between the assembly inlet and the first pump chamber, the first one way valve configured to permit fluid flow from the assembly inlet into the first pump chamber and to inhibit fluid flow from the first pump chamber toward the assembly inlet;
a second one way valve positioned in a fluid path between the first pump chamber and the assembly outlet, the second one way valve configured to permit fluid flow from the first pump chamber toward the assembly outlet and to inhibit fluid flow from the assembly outlet into the first pump chamber;
a third one way valve positioned in a fluid path between the assembly inlet and the second pump chamber, the third one way valve configured to permit fluid flow from the assembly inlet into the second pump chamber and to inhibit fluid flow from the second pump chamber toward the assembly inlet; and
a fourth one way valve positioned in a fluid path between the second pump chamber and the assembly outlet, the fourth one way valve configured to permit fluid flow from the second pump chamber toward the assembly outlet and to inhibit fluid flow from the assembly outlet into the second pump chamber, and wherein:
the offset cam is configured to push against the first drive wall in a first direction during the first portion of a rotation of the straight motor shaft and to push against the second drive wall in a second direction during the second portion of the rotation of the straight motor drive shaft, wherein the first direction and the second direction are collinear; and
(1) the first piston moves linearly toward the first diaphragm when the offset cam pushes against the first drive wall of the drive yoke in a manner which is collinear with the first direction and the second direction, and (2) the second piston moves linearly in a manner which is collinear with the first direction and the second direction.

2. The diaphragm pump assembly of claim 1 , comprising a motor shaft support positioned on a side of the drive yoke opposite the motor and configured to support the straight motor shaft.

3. The diaphragm pump assembly of claim 2 , wherein the motor shaft support includes an anti-friction bearing configured to engage the straight motor shaft and reduce friction between the straight motor shaft and the motor shaft support during rotation of the straight motor shaft.

4. The diaphragm pump assembly of claim 2 , comprising a housing within which the pump drive chamber is positioned, wherein the motor shaft support includes two pairs of attachments configured to attach the motor shaft support to the housing, wherein each pair of attachments spans the drive yoke in a direction parallel to the first drive wall and in a direction perpendicular to the first drive wall.

5. The diaphragm pump assembly of claim 1 , wherein the assembly includes only one load-bearing bearing for the straight motor shaft.

6. A diaphragm pump assembly comprising:
a first diaphragm chamber having an inlet, an outlet, and a first flexible wall;
a second diaphragm chamber having an inlet, an outlet, and a second flexible wall;
a pump drive chamber positioned between the first and second diaphragm chambers;
a drive yoke positioned within the pump drive chamber and having a first flat wall, a second flat wall parallel to and facing the first flat wall, a third wall connecting the first flat wall to the second flat wall, and a fourth wall opposite the third wall and connecting the first flat wall to the second flat wall;
a motor;
a straight motor shaft connected to the motor and extending into the pump drive chamber between the first and second flat walls and between the third and fourth walls of the drive yoke;
an offset cam configured to rotate in response to rotation of the straight motor shaft and positioned between the first and second flat walls;
a first piston connected to the first flexible wall and to the drive yoke; and
a second piston connected to the second flexible wall and to the drive yoke; wherein:
the offset cam is configured to push against the first flat wall in a first direction during a first portion of a rotation of the straight motor shaft and to push against the second flat wall in a second direction during a second portion of the rotation of the straight motor shaft, wherein the first direction and the second direction are collinear;
the first piston moves linearly toward the first flexible wall when the offset cam pushes against the first flat wall of the drive yoke, wherein linear movement of the first piston is collinear with the first direction and the second direction;
movement of the first piston toward the first flexible wall increases pressure within the first diaphragm chamber;
the second piston moves linearly away from the second flexible wall when the offset cam pushes against the first flat wall of the drive yoke, wherein linear movement of the second piston is collinear with the first direction and the second direction;
movement of the second piston away from the second flexible wall reduces pressure within the second diaphragm chamber;
the first piston moves away from the first flexible wall when the offset cam pushes against the second flat wall of the drive yoke;
movement of the first piston away from the first flexible wall reduces pressure within the first diaphragm chamber;
the second piston moves toward the second flexible wall when the offset cam pushes against the

Assignees

• Blue White Ind Ltd

Inventors

• Gledhill Iii Robert E
• Nguyen John

Classifications

• F04B43/026 Primary

  each plate-like pumping flexible member working in its own pumping chamber · CPC title

• F04B9/042

  the means being cams · CPC title

• F04B43/025 Primary

  two or more plate-like pumping members in parallel · CPC title

• F04B53/10

  Valves; Arrangement of valves · CPC title

• F04B7/0065

  being mounted on the main shaft · CPC title